Many methods have been described that purport to result in loss of weight in humans, specifically in the loss of body fat. However, data to support claims of easily and safely losing large amounts of weight is suspect in many cases, if it even exists. Of methods for which data has been published, five are well known:
(a) Caloric restriction. The person simply consumes fewer calories than usual each day. This can produce substantial weight loss over a few months, but the hunger it causes is intolerable over longer intervals. After a year, a substantial amount of the lost weight is regained and over a five-year period almost all of the lost weight is regained. Nevertheless, this method is still sometimes advocated, such as by Weight Watchers.
(b) Exercise. If a completely sedentary person becomes more active, a substantial amount of weight can be lost with moderate amounts of exercise. For anyone who already does a moderate amount of exercise—and many of these people want to lose more weight—it is very difficult to lose more weight by exercising more.
(c) Reduce fat intake. Reducing the percentage of calories from fat for most people causes only a small loss of weight.
(d) Surgery. In cases of extreme obesity, shortening the intestine causes substantial weight loss. This method, however, is dangerous, so dangerous that it is rarely used.
(e)Drugs. These are dangerous. The latest drug prescribed for weight loss, called fen-phen, was taken off the market after it was discovered to cause heart abnormalities.
Thousands of books have been published advocating methods of losing weight. Almost always there is no data to support the claims. Nevertheless, there may well be something to one method—eating a low-glycemic-index diet—advocated by three recent books, The Zone (Sears, 1995), Eat Yourself Slim (Montignac, 1999), and Sugar Busters (Steward, Bethea, Andrews, & Balart, 1998). (The glycemic index is a measure of how fast carbohydrates are digested. A low-glycemic-index diet emphasizes carbohydrates that are digested slowly, such as legumes. Examples of legumes are beans and lentils.) A large survey (Ludwig et al., 1999) found that people who ate a lot of fiber (highest quintile of fiber intake) weighed about 8 lb. less than people who ate little fiber (lowest quintile of fiber intake). Fiber intake and glycemic index are closely connected—foods with more fiber have lower glycemic indices. As part of testing the theory that led to the invention described here, I tried eating a low-glycemic-index diet and lost 6 lbs. So it is likely that a low-glycemic-index diet can produce a moderate weight loss in many people.
In view of the difficulty in obtaining and sustaining weight loss in individuals, new techniques that provide for weight loss and that are supported by scientifically valid evidence are greatly desired. The method of the invention provides an easy way to lose a large amount of weight (specifically body fat). It does not require going hungry, exercise, surgery, drugs, elimination of any specific food type from the diet, or ingestion of anything unpleasant or unusual. It can be used to maintain a lower weight indefinitely. Current methods of losing large amounts of weight are much more difficult, and the most common methods—eating less and exercise—can rarely be used to lose a large amount of weight for a long period of time.